This invention relates to an optical system which may be employed as a stand alone unit or for use with a device for attaching modular electronic components to or removing them from a substrate such as a printed circuit board.
Present day devices for removing or installing surface mounted electronic components from a substrate such as a printed circuit board include those which use a blast of hot air to melt the solder. In particular, these devices direct a blast of hot air at the terminals from the source above the component to simultaneously melt the solder on each. Such a device, for example, is disclosed in the above-mentioned co-pending application Ser. No. 649,065. Since the components are becoming increasingly smaller, and their proximity to one another on the printed circuit board is increasing, the above device not only provides a closely controlled and evenly distributed source of hot air sufficient to melt solder associated with component terminals or printed substrate conductors during installation or removal of the electronic component relative thereto but also rapidly and precisely directs this controlled hot air where desired via a nozzle or the like thereby minimizing the likelihood of meIting the solder on the terminals of adjacent components or otherwise damaging the printed conductors on the substrate. The nozzle typically closely surrounds the component but is slightly spaced therefrom. From the foregoing, it can be seen a surface mounted component to be installed must have the terminals thereof precisely aligned with the ends of the printed conductors or pads on the board to insure no overlapping occurs and/or no solder is smeared on the substrate between the conductors printed thereon. In order to insure alignment of the component terminals with the printed conductors, it is necessary to view at least three sides of the component or chip. After proper alignment has been effected, the component will then be soldered to the board with the device of the copending application Ser. No. 649,065. An inspection must then be made to determine whether there are any misaligned, shorted, or poorly soldered areas or any non-contacting leads. This inspection procedure may require viewing of all four sides of the component. Hereafter, the term "alignment" applies to the procedure, as described above, which occurs prior to soldering of the component to the board while "inspection" occurs after the soldering procedure.